<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Title</title>
    <script src="../vueJS/VUE.js"></script>
</head>

<body>
    <div id="root">
        姓：<input type="text" v-model:value="xing">
        <br>
        名：<input type="text" v-model:value="name">
        <br>
        姓名：{{a()}}
    </div> 
    <script type="text/javascript">
    Vue.config.productionTip = false
    new Vue({
        el:'#root',
        data:{
            xing:'张',
            ming:'三'//data里面属性的this是window
            
        },
        methods:{
            a(){
                return this.xing+this.ming
            }
        }
    })
    </script>
</body>
</html>